The extent of the 192.168.0.0 network depends on the network mask configured. For example, 192.168.0.0/16 represents the private network with IP address range 192.168.0.0 - 192.168.255.255. Broadband routers more often use the Class C default 192.168.0.0/24 mask with range 192.168.0.0 - 192.168.0.255. Routers on these networks conventionally use IP address 192.168.0.1.
Being private, 192.168.0.0, 192.168.0.1 and all other addresses within this network cannot be used on the Internet.
More: 192.168.1.0 private network
See also: What's My IP Address?